Cotton Sub-Irrigation

Transcript

Chuck Denney, Narrator (UT Institute of Agriculture)
This cotton plant aspires to be a tree. Little does it know that later this fall, we’ll end its growth and harvest it for its white fruit.

Dr. Chris Main (UT Extension)
“So what this plant does is it grows vegetatively until it gets to a point that says, ‘Okay, I’ve got enough mass now, I can reproduce.”

Chuck Denney
But to reproduce and grow tall, it needs moisture. Cotton likes it hot, but not dry. So just water it, right? Irrigation is a possibility – and sometimes a necessity – but it can be costly to farmers.

Dr. Chris Main
“We want to be able to put the irrigation on the acres that’s going to be the most beneficial.”

Chuck Denney
Dr. Chris Main with UT Extension helps cotton producers with irrigation to keep crops healthy in dry weather. Main and other experts are experimenting with sub-irrigation or drip systems, like this one they installed at the UT AgResearch center in Jackson. Here a series of thin-walled plastic tubes are buried between rows about a foot underground. The tubes then are slowly pressurized to drip water into the soil, where it’s really needed.

Dr. Chris Main
“What’s nice about that system is you eliminate the evaporative losses, so it’s more efficient from a water use standpoint.”

Chuck Denney
Farmers in the past shied away from above ground irrigation because of sloped fields and water runoff. But with sub-irrigation keeping the action below the surface, there’s much less soil loss and it’s better for our environment.

Sub-irrigation means there’s no pounding from rain or pivot irrigation machines, and less erosion. Sometimes pivot systems are the best way to water a field, but a cotton producer growing one thousand acres can easily spend one hundred thousand dollars in irrigation alone.

Dr. Brian Leib (UT Biosystems Engineering)
“The bigger fields are more cost effective for a pivot. But if you start looking at odd-shaped small fields, well, the pivot isn’t cost effective anymore. So there you could say, for the same price, I could put in a drip system.”

Chuck Denney
Sub-irrigation could be the answer farmers are looking for in the future. If we’re to grow cotton under challenging conditions, we must find ways to water plants. And as this hot, dry growing season comes to a close, a little mud in between cotton rows is a welcome site.

NOTE: UT experts say they’re also researching variable rate irrigation – where soil types determine how much water a field should receive.